JP2015086677A - Construction method for multiply extendable permanent anchor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction method for a multiply extendable permanent anchor capable of maximizing bearing power using the frictional resistance of an anchor body and the bearing pressure of an extending anchoring part by multiply extending an anchor using a first extending wedge and a second extending wedge and separating the top and the bottom of the extending wedges from each other at regular intervals.SOLUTION: The construction method for a multiply extendable permanent anchor can achieve firm close contact and frictional support force even in a ground largely weathered or in a crushed ground as well as in a base rock, by multiply extending an anchor body in a system of primary extension by the first impact added to a striking head, secondary and tertiary extension by tensile force added to a steel stranded wire.

Description

  The present invention relates to a method for constructing a multi-expansion permanent anchor, and more specifically, a multi-expansion wedge and a secondary expansion wedge are expanded multiple times. It is related with the construction method of the multiple expansion permanent anchor which can maximize the support force by exhibiting the friction resistance force of this and the supporting pressure of the expanded fixing part.

  Ground anchors are classified into permanent anchors that are applied to permanent structures depending on the period of use and purpose, and temporary anchors that are generally used for a period of less than two years, and are friction type, bearing type, composite type according to the support system for the ground. Etc., and according to the support method by the grout of the tensile material, it is classified into a tension type, a compression dispersion type, a compression concentration type, and the like.

  Moreover, it classify | categorizes with a PC steel twisted wire anchor, a steel bar anchor, a landfill-type anchor, a removal-type anchor, etc. by the kind of tension | tensile_strength material, a use application, etc.

  As described above, in order to secure the tensile force, which is the most important reason why ground anchor methods are classified in various ways, construction methods and material selection that meet the ground conditions must be established.

  Currently, the construction sequence normally applied is that a drilling hole having a diameter of about 105 mm is formed by drilling equipment, an anchor having a length of about 10 to 30 m is inserted inside the drilling hole, and then grouting is performed for a curing period. After passing through, the construction wall body and the anchor are fixed, and the construction is established by a procedure of applying a prestress of about 30 to 80 ton and stabilizing it.

  This is because the tensile force is secured only by the frictional force between the cross-sectional area and the grout purely, so if the formation is weak, the frictional force is inferior and it is difficult to ensure the tensile force, so an excessive design ( There is a problem that the construction period will be extended and the construction cost will increase due to the increase in quantity) and the supplemental (deformation) method.

  In addition, there is a kind of permanent anchor that is named bearing type anchor and applied to the rock layer, but this has the advantage that it can secure tensile force even if the length is shorter than other anchors, but it is weak. It is impossible to apply in the layer, the product unit price is very high, and it is generated by eliminating the worker's avoidance phenomenon and the additional process due to the principle that the effect is demonstrated when the additional process is artificially added in the construction This is a situation that is applied in a trivial manner.

  As described above, the existing technology lacks technicality and economy, and it is difficult to ensure smooth workability in any formation.

  Above all, there is a problem that it is difficult to maintain the frictional resistance by touching the hole wall with only a part of the anchor body that is not expanded at equal intervals.

  As a technique for solving the above-mentioned problems, the patent of the present applicant, “an expanded bearing type anchor that can be pulled even in the crushing ground (Korean Registered Patent Publication No. 10-1222477, Patent Document 1). ) Has a main body having fastening grooves so that a large number of anchor bodies are fastened to the outer peripheral surface, a hole expanding body fastened to the tip of the main body, and an insertion hole formed in the center by being fastened to the tip of the main body. A cap, a support plate is formed at the front end by being inserted into the insertion hole of the cap, and an insertion protrusion formed at the rear end is constituted by a striking bar inserted and installed in the insertion groove of the expansion body, A friction groove for generating a frictional force on the outer surface is formed so as to correspond to the inner surface of the shoulder of the enlarged hole, an insertion groove having an inclined surface is formed in the center of the inside, and a guide shaft is formed on the outer surface. A large number of split types with a guide groove inserted Configuration is Publishing with.

  The configuration as described above is to form a drilled hole vertically or tilting using a hammer beat on ground above weathered rock, and after expanding the tip of the drilled hole to form a hole with a shoulder When the anchor is inserted, it slides down according to the weight of the anchor and the angle of the drill hole, so that the support plate of the striking bar installed at the tip of the main body collides while touching the bottom surface of the tip of the hole Become. At this time, the insertion protrusion fastened to the rear of the striking bar moves vertically upward, and the expanded hole body opens while spreading outward around the guide shaft. In this state, the steel stranded wire is pulled upward. After that, the groove for friction formed on the outer surface of the expanded hole body is in the middle of the expanded groove, and it is fixed by being recessed into the shoulder and inner surface of the expanded hole. Was to be implemented.

  However, in Patent Document 1, since the expansion body is limited to spread outward by the insertion protrusion having the wedge shape or the expansion body is limited to spread, the friction groove of the expansion body is formed on the outer wall of the expansion hole. There was a problem of poor adhesion.

  In addition, there is a problem in that it is not possible to adjust the spacing between the expanded body.

  In addition, according to the patentee's patent “Method for constructing a hole-bearing support anchor” (Korean Registered Patent Publication No. 10-0993575, Patent Document 2), the anchor is inserted into the hole and the impact of the slide bar is increased. After the fixing, the expanded wings are spread, and after the provisional tensioning, a structure constituted by the procedures of grouting, main tensioning and deadlines has been disclosed.

  In the above technique, the quality of the grout is liked by pre-tensioning before the grout.

  However, in the above technique, the size of the expanded wing is small and the contact area is small, and further, only the expanded wing portion is closely attached to the inclined portion of the expanded hole, so that the expanded hole ground is severely weathered, or In the case of crushed ground, there is a problem that sufficient support force cannot be exhibited.

Korean Registered Patent No. 10-1222477 Korean Registered Patent No. 10-0993575

  The present invention is a technique proposed to solve the above-mentioned problems. The object of the present invention is to perform primary expansion by a first impact applied to a striking head, secondary and tertiary by a tensile force applied to a steel stranded wire. By expanding the anchor body in multiple ways by the expansion method, the multi-expansion permanent anchor that can have firm adhesion and frictional support force, especially in the case of rocky ground as well as severely weathered or crushed ground Provide construction methods.

  Another object of the present invention is to uniformly distribute the frictional resistance between the anchor body and the hole wall by having a structure in which the upper and lower portions of the anchor body are expanded at equal intervals by the hole expansion hole. The present invention is to provide a construction method for a multi-expansion permanent anchor that can exert a maximum bearing pressure and include a peripheral frictional resistance force by a grout to greatly advance a supporting force.

  Still another object of the present invention is to provide a striking bar with a striking wedge, a primary expansion wedge, and a secondary expansion wedge connected to the top, middle, and bottom, respectively. The secondary expansion wedge is supported in contact with the upper, middle, and lower portions of the anchor body, so that the upper and lower portions of the anchor body expand with a certain width, thereby expanding the peripheral surface of the expanded hole. It is an object of the present invention to provide a method for constructing a multi-expansion permanent anchor that can evenly disperse the frictional resistance between the anchor body and the hole wall around the entire anchor body.

  Still another object of the present invention is that the primary expansion wedge is primarily expanded while the upper inclined portion of the primary expansion wedge moves upward along the inclined guide portion inside the anchor body due to the impact of the hitting bar hitting the bottom surface of the drill hole. When a tensile force is applied to the steel stranded wire, the anchor body is expanded while moving upward, and the striking wedge is secondarily expanded while being disengaged from the top of the striking wedge insertion hole. Of course, the anchor body is expanded by applying a tensile force, and the wing locking projection is horizontally expanded in the third order while detaching the locking projection insertion hole, so that the supporting force can be increased through multiple expansion. In addition, since the upper end of the anchor body is indented into close contact with the upper part of the expansion hole by forming protrusions due to the third horizontal expansion, the multi-expansion permanent anchor can exhibit a firmer support force. It is to provide a construction method.

  Still another object of the present invention is to maximize the support force by expanding multiple times when the anchor body is struck into the hole, and when the steel stranded wire is pulled out. By maintaining the contact area evenly, the anchor body expands horizontally and sinks into the ground so that the upper end of the anchor body rests on the ground. To provide a method for constructing multiple extended permanent anchors that can increase the resistance force, maximize the support pressure in the hole expansion hole, and increase the anchor force by energizing the peripheral friction resistance force by the grout. is there.

The multi-expansion permanent anchor construction method according to the present invention for accomplishing the above-described object is a permanent anchor construction method in which the diameter is gradually reduced at the lower portion of the perforation hole 2 while drilling the target ground using an expansion beat. An expanding hole forming step of forming an increasing shoulder 3 and an expanding hole 4 having a constant inner diameter at the lower portion of the shoulder 3; an inclined portion that is capable of multiple expansion in the horizontal direction and inclined upward The anchor body 10 formed with 12, the striking bar 70 installed at the lower part of the anchor body 10, and connected to the striking bar 70, the anchor body 10 is expanded in multiple while moving to the inside of the anchor body 10. An anchor insertion step of preparing a multi-expansion permanent anchor including a wedge to which a steel stranded wire 1 is connected and inserting it into the perforated hole 2; A primary expansion stage in which the anchor body 10 is primarily expanded while the wedge moves to the inside of the anchor body 10 by hitting the bottom 70 of the hole 4; and the steel stranded wire 1 connected to the wedge is primarily The anchor body 10 is moved in the vertical direction while the anchor body 10 is secondarily horizontally expanded by pulling and lifting the rust, so that the side wall surface of the anchor body 10 is expanded hole 4.
A secondary expansion stage in which the inclined portion 12 of the anchor body 10 is in close contact with the wall surface, and the inclined portion 12 of the anchor body 10 is in close contact with the shoulder portion 3; 10 is horizontally expanded, and the side wall surface and the inclined portion 12 of the anchor body 10 are embedded in the expanded hole 4 and the shoulder 3 in the horizontal direction, or are in close contact with the expanded hole 4 and the shoulder 3 in the horizontal direction. A third expansion step, a grouting step for putting a grouting solution into the perforation hole 2 and curing, and a deadening step for installing a cap on the upper portion of the perforation hole 2 to perform a deadline process. It is characterized by that.

  At this time, the multiple extended permanent anchor has a number of steel stranded wire insertion holes 11 formed in the vertical direction at the upper end, and an inclined portion 12 inclined so that the outer diameter gradually increases on the upper outer peripheral surface. A plurality of tightening ring insertion grooves 13 are formed on the outer peripheral surface at the lower portion of the inclined portion 12, and the tightening ring 13a is installed around the inside. A hollow portion is formed from the upper portion to the lower portion inside. However, the hollow portion has a hitting wedge insertion hole 14 in which a locking projection 14a is formed in the upper portion sequentially from the upper side to the lower side, and a locking projection insertion hole 15 which is spaced apart from the hitting wedge insertion hole 14, An inclined guide portion 16a that is inclined so that the inner diameter gradually decreases in the upper direction is formed, and a lower inner peripheral surface of the inclined guide portion 16a is configured by an extended wedge guide hole 16 that is formed vertically. In the vertical direction An anchor body 10 which is divided by a large number of units 10a with respect to an axis; and is inserted and installed in the hammering wedge insertion hole 14, and a steel twist so as to be aligned with the steel stranded wire insertion hole 11 on the outer peripheral surface. A striking wedge 20 in which a line guide groove 21 is formed in a vertical direction, and a locking portion 22 protruding outward is formed on the outer peripheral surface of the lower portion so as to cover the locking protrusion 14a; A steel stranded wire through hole 31 is formed in a vertical direction so as to be aligned with the steel stranded wire insertion hole 11, and a first striking bar through hole 32 is formed in the center. The formed wing locking projections 30 are inserted and installed in the extended wedge guide holes 16, and the upper inclined portion 41 having the same inclination angle as the inclined guide portion 16a is formed on the outer peripheral surface on the upper side. And the upper part A vertically formed vertical portion 42 is formed in the lower portion of the inclined portion 41, and a second hitting bar through hole 43 is vertically formed in the center, and the steel stranded wire insertion hole 11 is formed. A primary extended wedge 40 in which a steel stranded wire fastening hole 44 is formed to connect a lower portion of the steel stranded wire 1 installed through the steel stranded wire guide groove 21 and the steel stranded wire through-hole 31; A third striking bar through-hole 51 that is in line with the two striking bar through-holes 43 is formed, and a first sloping surface 52 that is slanted from the upper and lower sides is formed on the whole or a part of the outer peripheral surface. A secondary expansion wedge 50 whose upper part is connected to the primary expansion wedge 40; and is divided into a plurality of parts based on a central axis in the vertical direction and fastened to the lower ends of the units 10a of the anchor body 10; In the center, the third hitting bar through hole 51 is provided. The extended wedge insertion hole 61 is formed in a straight line with the extended wedge insertion hole, and the extended wedge insertion hole has a second inclined angle that is equal to the first inclined surface 52 of the secondary extended wedge so as to have a lower slope. An extended feather cutting plate 60 on which a surface 61a is formed; the upper part is connected to the striking wedge 20 and the lower part is projected to the outside of the third striking bar through hole 51 of the secondary expansive wedge 50 And a striking bar 70 having a striking head 71 connected to the lower end thereof.

  Further, in the primary expansion step, the first inclined surface 52 of the secondary expansion wedge 50 connected to the striking bar 70 by striking the striking bar 70 below the permanent anchor to the bottom of the hole 4 is an expanded feather clamping plate. The upper inclined portion 41 of the primary expansion wedge 40 connected to the secondary expansion wedge 50 is moved upward on the second inclined surface 61 a of the inner peripheral surface of the 60 expansion wedge insertion holes 61, and the anchor body 10 is inclined. The anchor body 10 is lifted while being in contact with the guide portion 16a so that the anchor body 10 is primarily expanded horizontally while maintaining equal intervals in the vertical direction, but the striking wedge 20 connected to the top of the striking bar 70 is locked. The secondary expansion step is performed by first pulling the steel stranded wire 1 and pulling the primary expansion wedge 40 and the secondary expansion wedge 50 upward to make the primary expansion. While the tension wedge 40 rises on the inclined guide portion 16 a, the anchor body 10 is secondarily expanded horizontally, the wing locking projection 30 is pushed up, and the upper end of the wing locking projection 30 becomes the upper end of the locking projection insertion hole 15. As the anchor body 10 is moved upward, the side wall surface of the anchor body 10 is brought into close contact with the wall surface of the enlarged hole 4, and the inclined portion 12 is brought into close contact with the shoulder portion 3; The primary extension wedge 40 and the secondary extension wedge 50 are pulled upward by pulling the wire 1 to the secondary tension, and the primary extension wedge 40 pushes up the wing locking projection 30 to insert the wing locking projection 30 into the locking projection insertion hole. 15 while being moved to the upper portion of 15, the lower vertical portion 42 of the primary expansion wedge 40 is thirdarily expanded horizontally so as to be in contact with the lower end corner of the locking projection insertion hole 15, and the side wall surface of the anchor body 10 and Inclined part 12 is expanded hole It is characterized in that it is embedded in the tool 4 and the shoulder 3 in the horizontal direction or is in close contact with the hole expanding hole 4 and the shoulder 3 in the horizontal direction.

  According to the present invention, the rock body is particularly severely weathered by extending the anchor body in multiple ways by primary expansion by the first impact applied to the striking head and secondary and tertiary expansion by the tensile force applied to the steel stranded wire. In addition, even in the case of crushed ground, it has a firm adhesion and frictional support.

  In particular, by having a structure in which the upper and lower parts of the anchor body are expanded at equal intervals in the hole expansion hole, the maximum support pressure is exhibited while the frictional resistance force between the anchor body and the hole wall is evenly distributed. Thus, the support force can be greatly advanced by including the peripheral frictional resistance force by the grout.

  More specifically, the striking bar is connected to the striking wedge, the primary expansion wedge, and the secondary expansion wedge at the top, middle, and bottom, respectively, and the striking wedge, the primary expansion wedge, and the secondary expansion are performed in the process of expanding the anchor body. The wedge is supported in contact with the upper, middle, and lower parts of the anchor body, so that the upper and lower parts of the anchor body expand with a certain width, thereby evenly sticking to the peripheral surface of the expanded hole. Thus, the frictional resistance between the anchor body and the hole wall can be evenly distributed around the entire anchor body.

  In addition, the impact of the striking bar hitting the bottom of the perforated hole causes the upper extended wedge to move upward along the inclined guide part inside the anchor body, causing the primary extended wedge to expand first, and pulling the steel stranded wire. In addition, the anchor body is expanded while moving upward, the striking wedge is secondarily expanded while being disengaged to the top of the striking wedge insertion hole, and the anchor body is additionally subjected to a tensile force applied to the steel stranded wire. In addition to being expanded, the wing locking protrusion is horizontally expanded in the third order while detaching from the locking protrusion insertion hole, so that the supporting force is increased through multiple expansion, as well as the protrusion by the third horizontal expansion is formed. Then, since the upper end of the anchor body is recessed and closely contacted with the upper portion of the expanded hole, it is possible to exhibit a firmer support force.

  That is, according to the present invention, when the anchor body hits the hole, the support force is maximized so that it is expanded multiple times when the steel stranded wire is pulled out, but the upper and lower parts of the anchor body are evenly expanded. By doing so, the contact area is maintained uniformly, and the anchor body expands horizontally and sinks into the ground so that the upper end of the anchor body is applied to the ground, thereby increasing the frictional resistance of the anchor body. Thus, the support pressure in the hole expansion hole is maximized, and the anchoring force can be greatly advanced by energizing the peripheral friction resistance force by the grout.

It is process drawing which showed the construction method of the multiple expansion permanent anchor by this invention. FIG. 5 is a cross-sectional view showing a hole forming step according to the present invention. FIG. 4 is a cross-sectional view showing an anchor insertion step according to the present invention. FIG. 3 is a cross-sectional view showing a primary expansion stage according to the present invention. FIG. 3 is a cross-sectional view showing a secondary expansion stage according to the present invention. FIG. 3 is a cross-sectional view showing a third expansion stage according to the present invention. FIG. 3 is an exploded cross-sectional view showing an embodiment of a multiple expansion permanent anchor used in the present invention. It is sectional drawing which showed the state by which the steel stranded wire was installed in the multiple expansion permanent anchor used by this invention. It is the disassembled perspective view which showed another Example of the secondary expansion wedge and expansion wing cut-off board by this invention. 6 is a photograph showing an embodiment in which a hitting wedge, a wing locking protrusion, a primary extension wedge, and a secondary extension wedge are connected to a hitting bar according to the present invention. It is the photograph which showed the state by which the components of FIG. 10 were inserted in the anchor body. It is the photograph which showed the installation state of components in the state which the steel strand wire was connected to the primary expansion wedge of FIG. It is the photograph which showed the expansion state of the anchor body by the movement of a primary expansion wedge and a secondary expansion wedge. It is the photograph which showed the expansion state of the anchor body by the movement of a primary expansion wedge and a secondary expansion wedge.

  Hereinafter, steps will be described in detail with respect to a method for constructing a multi-expansion permanent anchor according to the present invention through the attached drawings.

  The method for constructing a multiple expansion permanent anchor of the present invention is largely comprised of a hole expansion stage, an anchor insertion stage, a primary expansion stage, a secondary expansion stage, a tertiary expansion stage, a grouting stage, and a deadline stage.

1. Expanded hole formation stage

  As shown in FIG. 2, while the target ground is drilled by using the expanding beat, as shown in FIG. 2, the shoulder portion 3 gradually increases in diameter at the lower portion of the drilling hole 2 and has a constant inner diameter at the lower portion of the shoulder portion 3. And an expanded hole 4 having

  More specifically, a perforated hole is formed in a general bedrock layer, severely weathered or crushed ground, etc., using an expanded beat having a wing beat that is fastened to the bottom of the beat housing. .

  First, after setting the steel pipe to the ground at a predetermined depth, after installing and inserting a hammer drill and a hole-expanding beat inside the steel pipe, fasten the protective cap that protrudes inward to the tip of the steel pipe. Protect the tip of the wing beat inserted inside the tube.

  The extended beat mounted on the hammer drill is lowered downward along the inside of the steel tube, and the wing beat is lowered while being lowered to the lower portion of the beat housing by its own weight.

  In this state, if the expanded beat comes down to the inside of the steel tube and comes into contact with the ground through the protective cap, the wing beat protruding to the bottom stops on the ground.

  Then, if the expanding beat is further lowered to the lower part, the wing beat is expanded to the outside.

  When the beat housing is rotated in this state, the beat housing and the wing beat protruding to the outside of the outer diameter of the steel tube rotate together to form a section-perforated hole necessary for fixing.

  The diameter and length of the drill hole can be drilled in various forms depending on the working environment.

  The perforated hole can be vertically perforated and inclined perforated, and at the time of inclined perforation, the perforation hole is perforated so that the inclination angle is inclined downward 15 °.

2. Anchor insertion stage

  Multiple extension in the horizontal direction is possible, the anchor body 10 having the inclined portion 12 inclined upward, the striking bar 70 installed at the bottom of the anchor body 10, and the striking bar 70 are connected to each other. The anchor body 10 is expanded multiple times while moving into the anchor body 10 to prepare a multiple expansion permanent anchor configured to include a wedge to which the steel stranded wire 1 is connected.

  The prepared multiple expansion permanent anchor is inserted into the perforated hole 2 as shown in FIG.

  Examples of preferred permanent anchors are illustrated in the accompanying drawings. The permanent anchor in the attached drawing is a new concept anchor that has never existed, and will be described in more detail below.

  The permanent anchor used in the present invention is mainly configured to include an anchor body 10, a striking wedge 20, a wing locking projection 30, a primary expansion wedge 40, a secondary expansion wedge 50, an expansion wing closing plate 60, and a striking bar 70. ing.

  As shown in FIGS. 7 and 11, the anchor body 10 has a number of steel stranded wire insertion holes 11 formed in the vertical direction at the upper end.

  The steel stranded wire insertion hole 11 is formed while equally dividing the central axis while being spaced apart from the upper part of the hollow part to be described later in the outline direction.

  In FIG. 7, the cross section of the anchor body 10 is illustrated by a line perpendicular to the cross section, and in FIGS. 11 and 12, grooves 10 are formed on both sides of the inner peripheral surface of each unit 10 a constituting the anchor body 10. The units 10a are combined to form a hole shape.

  In such a configuration, it is only necessary to simply form a groove without punching a separate hole in each anchor body 10, so that member processing and manufacturing are facilitated.

  At the same time, an inclined portion 12 that is inclined so that the outer diameter gradually increases toward the lower side is formed on the upper outer peripheral surface.

  The lower portion of the inclined portion 12 is formed to have a constant diameter, but a plurality of fastening ring insertion grooves 13 are formed on the outer peripheral surface of the lower portion of the inclined portion 12. The fastening ring 13a is wrapped and installed.

  The fastening ring 13a can be formed of various members that serve to wrap the anchor body 10 and tighten it toward the center, such as a rubber ring or a spring.

  Furthermore, the outer peripheral surface of the anchor body 10 can be formed in various surface shapes such as a punching hole, a groove, and an embossing in order to increase the contact force.

  As shown in FIG. 12, the anchor body 10 is divided into a large number of units 10a based on the central axis in the vertical direction, and the divided units 10a are installed with fastening rings 13a wrapped around. As a result, a cylindrical shape is formed as a whole.

  On the other hand, the anchor body 10 is formed by a hollow portion whose inside is vacant from the upper portion to the lower portion, and this hollow portion is sequentially hit from the upper side to the lower side, the wedge insertion hole 14, the locking projection insertion hole 15, and the expansion wedge. A guide hole 16 is formed.

  As shown in FIG. 7, the hitting wedge insertion hole 14 is formed with a locking projection 14a on the top.

  Further, the striking wedge insertion hole 14 may be formed so that the inner diameter gradually increases as a whole from the top to the bottom, or the inner diameter is gradually increased in the lower section.

  The inclined shape is taken so that the hitting wedge 20 can move upward so as to slide in the hitting wedge insertion hole 14 by the upward movement of the hitting bar 70.

  As shown in the drawing, the locking projection insertion hole 15 is formed apart from the striking wedge insertion hole 14.

  At this time, the space between the locking projection insertion hole 15 and the striking wedge insertion hole 14 is larger than the outer diameter of the striking bar 70 so that the striking bar 70 can move sufficiently. While having a diameter smaller than 15, the inside is connected and connected.

  At this time, as shown in the drawing, the bottom surface of the locking projection insertion hole 15 is preferably formed with a locking projection guide portion 15a having a sectional shape inclined downward toward the center.

  3 is converted to the stage of FIG. 4 in FIG. 3, that is, when the striking head 71 touches the bottom of the enlarged hole and strikes, the wing engaging projection 30 is inclined at the bottom of the engaging projection insertion hole 15. This is because each unit 10a of the anchor body 10 naturally spreads while sliding on the locking projection guide portion 15a.

  The extended wedge guide hole 16 is formed with an inclined guide portion 16a inclined so that the inner diameter gradually decreases in the upward direction while being directly connected to the locking projection insertion hole 15.

  At this time, the lower inner peripheral surface of the inclined guide portion 16a is formed vertically.

  The striking wedge insertion hole 14, the locking projection insertion hole 15, and the extended wedge guide hole 16 are formed by dividing the anchor body 10 into a large number of units 10a. In the photograph of FIG. A groove shape is formed on the inner wall surface.

  The hammering wedge 20 is inserted and installed in the hammering wedge insertion hole 14 as shown in the figure, and a steel stranded wire guide groove 21 is perpendicular to the outer circumferential surface so as to be aligned with the steel stranded wire insertion hole 11. It is formed in the direction.

  Further, a locking portion 22 is formed on the outer peripheral surface of the lower portion so as to protrude outward so as to cover the locking protrusion 14a.

  Such a locking portion 22 is applied to the locking projection 14a before each unit 10a of the anchor body 10 is expanded, and the inner diameter of the locking projection 14a is larger than the outer diameter of the locking portion 22. When it becomes larger, the hitting wedge 20 is projected out of the hitting wedge insertion hole 14 and can be moved.

  As shown in the drawing, the hitting wedge 20 has a hitting bar fastening groove 23 formed in a lower portion thereof, and can be connected by being pinched while the upper end of the hitting bar 70 is screwed.

  As shown in FIGS. 7 and 10, the wing locking protrusion 30 is inserted and installed in the locking protrusion insertion hole 15, and penetrates the steel stranded wire so as to be aligned with the steel stranded wire insertion hole 11. The hole 31 is formed in the vertical direction, and a first hitting bar through hole 32 is formed in the middle of the hitting bar 70 in the center.

  Such a wing locking protrusion 30 can be slid up and down on the striking bar 70 by installing the striking bar 70 through the first striking bar through hole 32.

  Moreover, the steel stranded wire 1 is penetrated through the outer steel stranded wire through-hole 31, so that the steel stranded wire 1 can be moved up and down.

  As shown in FIG. 3, the wing locking protrusion 30 is inserted into the locking protrusion insertion hole 15 and cannot be moved up and down, but each unit 10a of the anchor body 10 is expanded or expanded. In this state, it can slide on the locking projection guide portion 15a, or it can be pushed by the primary expansion wedge 40 and moved to the striking wedge insertion hole 14 as shown in FIG.

  The primary expansion wedge 40 is inserted and installed in the expansion wedge guide hole 16 inside the anchor body 10 as shown in FIGS. 7, 8 and 10.

  At this time, the outer peripheral surface of the primary extended wedge 40 is formed with an upper inclined portion 41 having an inclination angle equal to that of the inclined guide portion 16a on the upper side, and the primary extended wedge 40 has an upper inclined portion 41 at the inclined guide portion 16a. It is configured to move with.

  At the same time, a vertically formed vertical portion 42 is formed below the upper inclined portion 41.

  In the center of such a primary extended wedge 40, a second striking bar through hole 43 is formed vertically and the striking bar 70 is penetrated and connected.

  Further, a steel stranded wire fastening hole 44 is formed to connect the lower portion of the steel stranded wire 1 installed through the steel stranded wire insertion hole 11, the steel stranded wire guide groove 21, and the steel stranded wire through hole 31. .

  At this time, as shown in the drawing, the steel stranded wire fastening hole 44 has a large lower diameter, a small upper portion, and a protrusion formed therebetween, and the lower portion of the steel stranded wire 1 has a shape corresponding thereto. Thus, when a tensile force is applied to the steel stranded wire 1 in the upward direction, the primary expansion wedge 40 receives a force to move upward together with the steel stranded wire 1.

  The secondary extended wedge 50 has a third hitting bar through hole 51 formed in a straight line with the second hitting bar through hole 43 in the center, the hitting bar 70 passes through, and the whole or part of the outer peripheral surface is A slanted first sloping surface 52 is formed, and the upper part is connected to the primary expansion wedge 40.

  The primary expansion wedge 40 is connected to the first expansion wedge 40 by increasing the lower inner diameter of the second striking bar through-hole 43 and then forming a screw thread on the upper outer periphery of the secondary expansion wedge 50. By forming a thread on the surface so as to be screw-coupled to the thread, the secondary expansion wedge 50 can be connected to the primary expansion wedge 40 by screw coupling.

  As shown in FIGS. 7, 11, and 12, the extended wing cut-off plate 60 is divided into a plurality of parts based on the central axis in the vertical direction and fastened to the lower ends of the units 10 a of the anchor body 10. Yes.

  As shown in the drawing, the first wing fastening hole 17 is formed in the lower portion of the anchor body 10, and the first volt fastening plate 60 has the first bolt fastening. A second bolt fastening hole 62 that is aligned with the fastening hole 17 is formed, and the fastening bolt 62a is passed through and connected to the two holes.

  A large number of such extended feather cut-off plates 60 are fixedly installed on each anchor body 10, and an extended wedge insertion hole 61 is formed in the center and in line with the third striking bar through hole 51.

  At this time, the extended wedge insertion hole 61 is formed with a second inclined surface 61a having a lower and upper width so as to have a gradient angle equal to that of the first inclined surface 52 of the secondary extended wedge 50. To do.

  The formation of the second inclined surface 61a in the expansion wedge insertion hole 61 means that when the second expansion wedge 50 is inserted through the expansion wedge insertion hole 61, the expansion blade closing plate 60 spreads smoothly. This is because the secondary expansion wedge 50 is smoothly inserted and raised.

  As shown in the figure, the hitting bar 70 has an upper portion connected to the hitting wedge 20 and a lower portion hitting the lower end while protruding to the outside of the third hitting bar through-hole 51 of the secondary expansion wedge 50. The head 71 is connected.

  As shown in the drawing, the striking head 71 is formed with a striking bar fastening hole 71a into which the bottom end of the striking bar 70 is inserted. The striking bar 70 is inserted into the striking bar fastening hole 71a while the bottom end of the striking bar 70 is inserted into the striking bar. A screw thread can be formed on the lower outer peripheral surface of 70 and the inner peripheral surface of the striking bar fastening hole 71a to be fixed by screwing.

  On the other hand, as shown in FIGS. 7 and 8, the fourth strike which is aligned with the second strike bar through-hole 43 in the center between the lower end of the primary extended wedge 40 and the extended feather cut-off plate 60. A buffer plate 80 formed with a bar through hole 81 and made of a stretchable material; installed at a lower portion of the buffer plate 80, and aligned with the fourth hitting bar through hole 81 in the center. It is desirable to install more extended wedge cut-off plates 90 in which five hitting bar through holes 91 are formed.

  The buffer plate 80 minimizes the transmission of the impact generated when the striking head 71 hits the bottom of the expanded hole to the anchor body 10 and the expanded wing cut-off plate 60 so that a smooth operation can be realized.

  As shown in the drawing, holes for fastening bolts are formed in the buffer plate 80 and the extended wedge cut-off plate 90. Therefore, after forming a hole in a straight line with the hole on the bottom surface of the primary extension wedge 40, it can be fixedly installed through the buffer plate fastening bolt 92.

  The multi-expansion permanent anchor having the above-described configuration is characterized in that when the anchor body 10 spreads, the upper portion and the lower portion spread from the center by the same distance.

  This is so that the upper striking wedge 20 connected to the striking bar 70, the intermediate primary expansion wedge 40 and the lower secondary expansion wedge 50 are in contact with the inner peripheral surface of the hollow portion of the anchor body 10 and the upper, middle and lower portions, respectively. Because it is, it will spread at equal intervals.

  Thus, if the anchor body 10 spreads at equal intervals, all the outer peripheral surfaces of the anchor body 10 come into contact with the inner wall surface of the expanded hole equally. As a result, a uniform supporting force is exhibited and the supporting force is improved.

  Furthermore, such a uniform support force can be exhibited even in a process in which the anchor body 10 is expanded over several times.

  To this end, as shown in FIG. 8, the length a of the first inclined surface 52 of the secondary expansion wedge 50 protruding from the lower portion of the expansion blade cutoff plate 60 is determined from the upper end of the primary expansion wedge 40. The distance (b) to the upper end of the inclined guide portion 16a of the anchor body 10 is equal to or longer than the distance (b), and the gradient angle of the first inclined surface 52 is compared with the gradient angle of the inclined guide portion 16a. It is desirable to have a slope angle of ± 1 °.

  Accordingly, when the primary expansion wedge 40 and the secondary expansion wedge 50 connected to each other rise together, as shown in FIG. 5, the upper inclined portion 41 of the primary expansion wedge 40 is anchored in the secondary expansion as shown in FIG. 10 in contact with the 10 inclined guide portions 16a, and at this time, the first inclined surface 52 of the secondary expansion wedge 50 is maintained in the state supported by the second inclined surface 61a of the extended closing blade 60, and the expansion is performed in an up and down uniform state. It becomes true.

  As another method, as shown in FIG. 9, the extended wedge insertion hole 61 of the extended wing cut-off plate 60 and the first inclined surface 52 of the secondary extended wedge 50 have grooves 63 and protrusions 52a that mesh with each other. It can be configured to be formed along the length direction so that the upper part and the lower part of the anchor body 10 are evenly expanded.

  At this time, as a method for increasing the ground contact force, the inner wall surface of the anchor body 10 and the outer peripheral surface of the primary expansion wedge 40 can still form grooves and protrusions.

3. Primary expansion phase

  The striking bar 70 below the permanent anchor is struck to the bottom of the hole 4 and the anchor body 10 is primarily expanded while the wedge moves into the anchor body 10.

  More specifically, when the permanent anchor is inserted downward in the state of FIG. 3, the impact head 71 collides while touching the bottom surface of the hole 4 while sliding down the inside of the hole. become.

  At this time, as shown in FIG. 4, the outer anchor body 10 is continuously lowered, and conversely, the first inclined surface 52 of the secondary expansion wedge 50 below the anchor body 10 Riding on the second inclined surface 61a on the inner peripheral surface of the extended wedge insertion hole 61 of the plate 60, the anchor body 10 is moved upward with reference to the primary extended wedge 40 connected thereto. The anchor body 10 ascends while in contact with the inclined guide portion 16a.

  In this state, the anchor body 10 is equidistantly spaced vertically by the primary expansion wedge 40 that rises on the inclined guide portion 16a and the secondary expansion wedge 50 that rises on the second inclined surface 61a of the lower expansion blade cutoff plate 60. While maintaining, the primary expansion will spread horizontally.

  At this time, the striking wedge 20 connected to the top of the striking bar 70 moves upward with respect to the anchor body 10 and moves to the top of the striking wedge insertion hole 14. This is the state.

  In the drawing, the diameter of the expanded hole 4 is shown to be larger than the outer diameter of the anchor body 10 that has been primarily expanded, but is the diameter of the expanded hole 4 equal to the outer diameter of the anchor body 10 that has been primarily expanded? In a small case, the anchor body 10 can be brought into close contact with the hole expansion hole 4 only by primary expansion.

  In such primary expansion, the anchor body 10 is expanded while the wedge 20 is lifted by the permanent anchor of the present invention only by a small impact due to its own weight. In this state, the primary expansion wedge 40 and the secondary expansion wedge 50 are anchors. When it becomes the position on the inclined wall surface inside the hollow portion of the body 10, expansion can be more easily established when the tensile force action of the steel stranded wire 1 that is carried forward is performed.

4). Secondary expansion phase

  The steel stranded wire 1 is pulled first, the wedge is raised, the anchor body 10 is secondarily horizontally expanded, the anchor body 10 is moved in the vertical direction, and the side wall surface of the anchor body 10 is the wall surface of the expanded hole 4. The inclined portion 12 of the anchor body 10 is brought into close contact with the shoulder portion 3.

  More specifically, as shown in FIG. 5, when the steel stranded wire 1 discharged to the outside of the perforated hole 2 is pulled using a tension machine, the lower end of the steel stranded wire 1 is connected to the primary extended wedge 40. Since they are connected, they are pulled upward by the primary expansion wedge 40 and the secondary expansion wedge 50.

  At this time, the primary extension wedge 40 rises on the inclined guide portion 16a and comes into contact with the bottom surface of the wing locking projection 30 installed inside the locking projection insertion hole 15, and then the wing locking projection 30 is moved. The wing locking projection 30 moves the anchor body 10 upward while the upper end of the wing locking projection 30 is over the upper end of the locking projection insertion hole 15.

  That is, during the secondary expansion, as in the primary expansion, the primary expansion wedge 40 and the secondary expansion wedge 50 expand the anchor body 10 vertically and uniformly while making contact with the anchor body 10 and the expansion wing shut-off plate 60, respectively. The expansion wedge 40 and the wing locking protrusion 30 are pushed up to move the anchor body 10 upward, and the inclined portion 12 of the anchor body 10 is brought into close contact with the shoulder portion 2 of the hole expansion hole 4.

5. Tertiary expansion phase

  The steel stranded wire 1 is secondarily pulled and the rust is additionally raised, so that the anchor body 10 is horizontally expanded, and the side wall surface and the inclined portion 12 of the anchor body 10 become the hole 4 and the shoulder 3. It sinks in the horizontal direction or is brought into close contact with the enlarged hole 4 and the shoulder 3 in the horizontal direction.

  More specifically, as shown in FIG. 6, if the steel stranded wire 1 is additionally pulled, the upper portion of the primary expansion wedge 40 passes through the locking projection insertion hole 15 and the lower portion of the striking wedge insertion hole 14. At this time, the wing locking projection 30 inserted into the locking projection insertion hole 15 is in a state in which the upper end is not applied to the locking projection insertion hole 15 due to the expansion of the anchor body 10, and the hitting wedge insertion hole It will be in a state of being seated at 14.

  That is, in the tertiary expansion, the upper portion of the primary expansion wedge 40 flows into the locking projection insertion hole 15 and the lower vertical portion 42 of the upper inclined portion 41 comes into contact with the lower corner of the locking projection insertion hole 15. Until the anchor body 10 expands horizontally.

  At this time, the anchor body 10 that expands horizontally applies pressure in the horizontal direction to the wall surface of the hole 4 and the shoulder 3, so in the case of weathered rock or soft rock fracture zone, the wall surface of the hole 4 In addition, the anchor body 10 enters the inside of the shoulder portion 3 so that a firm anchor force can be exerted even on the weak hole expansion hole 4.

  In FIG. 6, the first horizontal displacement 5 generated on the inner wall surface of the hole expansion hole 4 when the anchor body 10 sinks in the horizontal direction is indicated by a dotted line, and an anchor is placed above the first horizontal displacement 5. A second horizontal displacement 5a generated by the inclined portion 12 of the body 10 entering the inside of the shoulder portion 3 in the horizontal direction is shown by a dotted line.

  As described above, when the second horizontal displacement 5 a is generated, the upper end 18 of the anchor body 10 is brought into the inside of the shoulder portion 3 so that a firm supporting force can be exhibited.

  At this time, the diameter of the wing locking protrusion 30 is formed larger than the outer diameter of the primary expansion wedge 40, and the wing locking protrusion 30 is applied to the lower end of the expanded steel stranded wire insertion hole 11. desirable.

6). Grouting stage

  After the tensile force as described above is finished, the grout solution is put into the perforated hole 2 and cured.

  At this time, since the steel stranded wire 1 is maintained in a tensioned state through tensioning, no breakage occurs even after the grouting liquid has been cured.

  When the grouting is performed, the anchor body 10 is in contact with the wall surface of the expanded hole 4 evenly in the vertical direction, and is firmly pressed against the wall surface of the expanded hole 4 so that the frictional resistance of the anchor body 10 is increased. As a result, the supporting pressure of the hole 4 can be greatly exerted, and the peripheral frictional resistance force by the grout can be energized here, so that the supporting force of the anchor can be greatly advanced.

7). Deadline stage

  A cap is placed on the upper part of the perforated hole 2 and the deadline is processed.

  As an example of the deadline stage, after the grout is over, the head can be filled with grease, and then a separate cap can be installed to close the head.

  Various known deadline methods can be applied to the deadline processing step.

  The construction method of the multi-expansion permanent anchor according to the present invention is capable of multiple horizontal expansion, and primary horizontal expansion is achieved by striking the hole 4 of the striking wedge 20 using a permanent anchor that can move vertically in the middle. Subsequently, the anchor body 10 is firmly adhered to the wall surface of the hole 4 and the shoulder 3 by the secondary horizontal expansion and vertical movement due to the tensile force of the steel stranded wire, and then the tertiary expansion in the horizontal direction is established. As a result, it is possible to exert a firm adhesion on rock ground, and on a weak ground such as crushed ground, the anchor body 10 can sink into the wall surface of the expanded hole 4 and exert a sufficiently strong supporting force even on weak ground. .

  Although the present invention has been described in detail with reference to the embodiments, the present invention is not limited to the embodiments. The present invention does not depart from the spirit and spirit of the present invention as long as it has ordinary knowledge in the technical field to which the present invention belongs. The present invention may be modified or changed.

DESCRIPTION OF SYMBOLS 1 Steel twisted wire 2 Perforated hole 3 Shoulder part 4 Expanded hole 5 1st horizontal displacement 5a 2nd horizontal displacement 10 Anchor body
10a unit 11 steel stranded wire insertion hole 12 inclined portion 13 fastening ring insertion groove 13a fastening ring 14 striking wedge insertion hole
14a Locking protrusion 15 Locking protrusion insertion hole
15a Locking projection guide part 16 Extended wedge guide hole
16a Inclined guide portion 17 First bolt fastening hole 18 Upper end 20 Blowing wedge 21 Steel twisted wire guide groove 22 Locking portion 23 Strike bar fastening groove 30 Wing lock projection 31 Steel twisted wire through hole 32 First striking bar through hole
40 Primary expansion wedge 41 Upper slope
42 Vertical portion 43 Second hitting bar through hole 44 Steel twisted wire fastening hole 50 Secondary extended wedge 51 Third hitting bar through hole 52 First inclined surface 52a Protrusion 60 Extended feather closing plate 61 Extended wedge insertion hole 61a Second inclined surface 62 Second Bolt Fastening Hole 62a Fastening Bolt 63 Groove 70 Strike Bar 71 Strike Head 71a Strike Bar Fastening Hole 80 Buffer Plate 81 Fourth Strike Bar Through Hole 90 Extended Wedge Cut-off Plate 91 Fifth Strike Bar Through Hole 92 Shock Plate Fastening Bolt

Claims (3)

In the permanent anchor construction method,
While drilling the target ground using the expanding beat, a shoulder 3 having a diameter gradually increasing at the bottom of the drilling hole 2 and a expanding hole 4 having a constant inner diameter at the bottom of the shoulder 3 are formed. Expansion hole formation stage,
Multiple extension in the horizontal direction is possible, the anchor body 10 having the inclined portion 12 inclined upward, the striking bar 70 installed at the bottom of the anchor body 10, and the striking bar 70 are connected to each other. While moving to the inside of the anchor body 10, the anchor body 10 is expanded multiple times to prepare a multi-expansion permanent anchor including a wedge to which the steel stranded wire 1 is connected. An anchor insertion stage to insert;
A primary expansion step of primarily expanding the anchor body 10 while striking the striking bar 70 below the permanent anchor to the bottom of the hole 4 and moving the wedge into the anchor body 10;
The side wall surface of the anchor body 10 is moved by moving the anchor body 10 in the vertical direction while pulling the steel stranded wire 1 connected to the wedge first to raise the wedge and horizontally extending the anchor body 10 secondarily. A secondary expansion stage in which the inclined portion 12 of the anchor body 10 is in close contact with the shoulder portion 3 so as to be in close contact with the wall surface of the expanded hole 4;
The steel stranded wire 1 is secondarily pulled and the rust is additionally raised, so that the anchor body 10 is horizontally expanded, and the side wall surface and the inclined portion 12 of the anchor body 10 become the hole 4 and the shoulder 3. A tertiary expansion stage that either dives horizontally or is in close contact with the hole 4 and shoulder 3 in a horizontal direction;
A grouting step of putting a grouting liquid into the perforated hole 2 and curing the grouting liquid;
A deadline stage in which a cap is placed on the upper portion of the perforated hole 2 to perform a deadline process;
A method for constructing a multi-expansion permanent anchor characterized by comprising The multiple extended permanent anchor is
A number of steel stranded wire insertion holes 11 are formed in a vertical direction at the upper end, and an inclined portion 12 that is inclined so that the outer diameter gradually increases is formed on the upper outer peripheral surface. A number of tightening ring insertion grooves 13 are formed on the outer peripheral surface, and the tightening ring 13a is installed so that a hollow portion is formed inside from the top to the bottom. The striking wedge insertion hole 14 having a locking projection 14a formed in the upper part in the direction, the locking projection insertion hole 15 spaced apart from the striking wedge insertion hole 14, and the inner diameter gradually decreasing in the upward direction. The inclined guide portion 16a is inclined so as to be formed, and the lower inner peripheral surface of the inclined guide portion 16a is constituted by the extended wedge guide hole 16 formed vertically, and is based on the central axis in the vertical direction. In many units 10a An anchor body 10 which is divided,
A steel stranded wire guide groove 21 is formed in the vertical direction so as to be aligned with the steel stranded wire insertion hole 11 on the outer peripheral surface, and is inserted in the hitting wedge insertion hole 14, and on the lower outer peripheral surface. A striking wedge 20 formed with a locking portion 22 protruding outward so as to cover the locking protrusion 14a;
A steel stranded wire through-hole 31 is formed in a vertical direction so as to be aligned with the steel stranded wire insertion hole 11 and the first striking bar in the center. A wing locking protrusion 30 in which a through hole 32 is formed;
The extended wedge guide hole 16 is inserted and installed, and the outer peripheral surface is formed with an upper inclined portion 41 having an inclination angle equal to that of the inclined guide portion 16a on the upper side, and below the upper inclined portion 41, A vertical portion 42 formed vertically is formed, a second hitting bar through hole 43 is vertically formed in the center, and the steel stranded wire insertion hole 11 and the steel stranded wire guide groove 21 are formed. And a primary extension wedge 40 in which a steel stranded wire fastening hole 44 is formed, to which a lower portion of the steel stranded wire 1 installed through the steel stranded wire through hole 31 is connected, and
A third striking bar through-hole 51 is formed in the center in a straight line with the second striking bar through-hole 43, and a first inclined surface 52 that is slanted from the upper and lower sides is formed on the whole or part of the outer peripheral surface. A secondary expansion wedge 50 whose upper part is connected to the primary expansion wedge 40;
It is divided into a large number with respect to the central axis in the vertical direction and fastened to the lower end of each unit 10a of the anchor body 10, and an extended wedge insertion hole 61 that is aligned with the third striking bar through hole 51 at the center. However, the extended wing insertion hole is provided with a second inclined surface 61a having a lower and upper and lower width so as to have a gradient angle equal to that of the first inclined surface 52 of the secondary extended wedge. A deadline plate 60;
The upper portion is connected to the hitting wedge 20, and the lower portion is protruded to the outside of the third hitting bar through hole 51 of the secondary expansion wedge 50, and the hitting bar 70 is connected to the lower end of the hitting head 71. ,
The construction method of the multiple expansion permanent anchor of Claim 1 characterized by the above-mentioned. In the primary expansion step, the first inclined surface 52 of the secondary expansion wedge 50 connected to the striking bar 70 by striking the striking bar 70 below the permanent anchor 4 at the bottom of the hole 4 is formed on the extended feather cutting plate 60. The upper inclined portion 41 of the primary extended wedge 40 connected to the secondary extended wedge 50 is moved upward on the second inclined surface 61 a on the inner peripheral surface of the extended wedge insertion hole 61, and the inclined guide portion of the anchor body 10. The anchor body 10 is lifted while being in contact with 16a so that the anchor body 10 is primarily expanded horizontally while maintaining equal intervals in the vertical direction. However, the striking wedge 20 connected to the top of the striking bar 70 has a locking projection 14a. To move upward until the locking portion 22 is
In the secondary expansion step, the steel stranded wire 1 is first pulled, the primary expansion wedge 40 and the secondary expansion wedge 50 are pulled upward, and the primary expansion wedge 40 rises on the inclined guide portion 16a while being anchored. 10 is horizontally expanded, the wing locking protrusion 30 is pushed up, and the anchor body 10 is moved upward while the upper end of the wing locking protrusion 30 is resting on the upper end of the locking protrusion insertion hole 15, so that the anchor body 10 side The wall surface is in close contact with the wall surface of the expanded hole 4, and the inclined portion 12 is in close contact with the shoulder portion 3,
In the tertiary expansion step, the primary extension wedge 40 and the secondary expansion wedge 50 are pulled upward by causing the steel stranded wire 1 to be subjected to a secondary tensile force, and the primary expansion wedge 40 pushes up the wing locking protrusion 30 to lock the wing. While the projection 30 is moved to the upper part of the locking projection insertion hole 15, the vertical extension 42 at the lower part of the primary expansion wedge 40 is thirdarily expanded horizontally so as to be in contact with the lower corner of the locking projection insertion hole 15. Thus, the side wall surface and the inclined portion 12 of the anchor body 10 are embedded in the expanded hole 4 and the shoulder portion 3 in the horizontal direction, or are in close contact with the expanded hole 4 and the shoulder portion 3 in the horizontal direction. The construction method of the multiple expansion permanent anchor of Claim 2.

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